Analysis of spatiotemporal variations in land use on the Loess Plateau of China during 1986-2010

Conservation measures have been implemented on the Loess Plateau of China (CLP) to change land use patterns and control severe soil erosion. However, the effectiveness of these measures over the entire region has rarely been evaluated. The study aims to analyze the spatiotemporal variations in land use, provide a framework for evaluating the performance of conservation measures, and assist decision-making processes. Land use maps of 1986, 1995, 2005, and 2010 were used to analyze the land use changes (LUC) in terms of three indices: change magnitude (CM), change speed (CS), and change type (CT). As soil erosion is closely related to topography, the relationship between elevation, slope, and LUC was examined to assess the effectiveness of LUC. Results showed that during 1986-2010, farmlands and unused land decreased, while built-up land and forests increased. Although CM, CS, and CT were low during the study period spanning 1986-2010, the highest values were recorded during 1995-2005 indicating that soil conservation measures accelerated LUC in that period. Analysis of the relation between topographical factors and LUC revealed that the decrease in farmlands was more at higher elevations and/or steeper slopes, where forests tended to substitute farmlands. Human activities have played a major role in LUC in the CLP, but the process is probably accelerated by climate change.